YOKOGAWA PH72, Руководство пользователя

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IM 12B03D02-01E
6-1
6 . Maintenance
6. Maintenance
6.1 For Optimum Meter Performance
The Model PH72 Personal pH/ORP Meter is simple to operate, but is a precision
instrument. To ensure accurate results from the meter, the following precautions
should be observed.
Flow Diagram
Measurement
Maintenance Calibration
Storage
F060101.ai
Table 6.1 Precautions in Each Step
Calibration Calibration using standard solutions:
• 1- or 2-point calibration. 2-point calibration is recommended for
accurate pH measurement.
• Always use certified standard solutions (pH 2, 4, 7, 9, 10, or 12).
Measurement Sample solution requirements:
• pH range: 0 to 14 pH
• Temperature: 0 to 80°C (0 to 100°C when using needle type or
test tube size pH sensor)
Maintenance • After measurement, rinse off remaining sample solution from the
electrode thoroughly.
Storage • Avoid a place with high temperature and humidity.
• Keep the wetting cap (moisten the cotton wad in the cap with a
few drops of water) attached to prevent the glass electrode and
liquid junction from drying out.
6.2 pH Electrode Cleaning
Dirt or deposits on the glass electrode or liquid junction can often interfere with
accurate measurement. Periodical cleaning is required depending on the nature of
the solution being measured.